add methods

hutool-core/src/main/java/cn/hutool/core/convert/AbstractConverter.java

@@ -53,7 +53,7 @@ public abstract class AbstractConverter<T> implements Converter<T>, Serializable
 		if (null == defaultValue || targetType.isInstance(defaultValue)) {
 			if (targetType.isInstance(value) && false == Map.class.isAssignableFrom(targetType)) {
 				// 除Map外，已经是目标类型，不需要转换（Map类型涉及参数类型，需要单独转换）
-				return (T) targetType.cast(value);
+				return targetType.cast(value);
 			}
 			T result = convertInternal(value);
 			return ((null == result) ? defaultValue : result);

hutool-core/src/main/java/cn/hutool/core/io/FastByteArrayOutputStream.java

@@ -34,6 +34,7 @@ public class FastByteArrayOutputStream extends OutputStream {
 		buffer = new FastByteBuffer(size);
 	}
 
+	@SuppressWarnings("NullableProblems")
 	@Override
 	public void write(byte[] b, int off, int len) {
 		buffer.append(b, off, len);
@@ -52,7 +53,7 @@ public class FastByteArrayOutputStream extends OutputStream {
 	 * 此方法无任何效果，当流被关闭后不会抛出IOException
 	 */
 	@Override
-	public void close() throws IOException{
+	public void close() {
 		// nop
 	}
 

hutool-core/src/main/java/cn/hutool/core/util/CharUtil.java

@@ -244,6 +244,7 @@ public class CharUtil {
 	 * @return true表示为字符类
 	 */
 	public static boolean isChar(Object value) {
+		//noinspection ConstantConditions
 		return value instanceof Character || value.getClass() == char.class;
 	}
 
@@ -283,13 +284,14 @@ public class CharUtil {
 	 * @since 4.0.8
 	 */
 	public static boolean isEmoji(char c) {
+		//noinspection ConstantConditions
 		return false ==  ((c == 0x0) || //
 				(c == 0x9) || //
 				(c == 0xA) || //
 				(c == 0xD) || //
 				((c >= 0x20) && (c <= 0xD7FF)) || //
 				((c >= 0xE000) && (c <= 0xFFFD)) || //
-				((c >= 0x10000) && (c <= 0x10FFFF)));
+				((c >= 0x100000) && (c <= 0x10FFFF)));
 	}
 	
 	/**
@@ -319,4 +321,14 @@ public class CharUtil {
 		}
 		return c1 == c2;
 	}
+
+	/**
+	 * 获取字符类型
+	 * @param c 字符
+	 * @return 字符类型
+	 * @since 5.2.3
+	 */
+	public static int getType(int c){
+		return Character.getType(c);
+	}
 }

hutool-core/src/test/java/cn/hutool/core/util/CharUtilTest.java

@@ -20,4 +20,10 @@ public class CharUtilTest {
 		Assert.assertTrue(CharUtil.isEmoji(a.charAt(1)));
 		
 	}
+
+	@Test
+	public void isCharTest(){
+		char[] a = new char[]{'a'};
+		Assert.assertTrue(CharUtil.isChar(a));
+	}
 }